Current collector



Nov. 12, 1940. w. scm-.AKE

CURRENT COLLECTOR Filed Nov.

` WITNEssEs:

Patented' Nov. 12,` 1940 PATENT GFFICE CURRENT COLLECTOR William Schaake, Pittsburgh, Pa., assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporation -of Pennsylvania Application November 22, 1938, Serial N0. 241,789

14 Claims. (Cl. 191-55) My invention relates, generally, to current collectors and, more particularly, to collector shoes for current collectors of the pantograph type or the like.

- It is generally an object of my inventiony to provide a current collector shoe of the pantograph type having removable contact members of carbonaceous material.

More specifically it is an object of my invention l0 to provide a current collector shoe having removable contact members of carbonaceous material, and guard members for reinforcing the contact'members to prevent chipping and grooving y thereof.

' U Another object of my invention is to provide for securing a plurality of contact members of carbonaceous material in the body member of a collector shoe of the pantograph type and conducting current therefrom independently of the body member.

' A further object of my invention is to provide for reinforcing the normally exposed edges of carbon contact members in a collector shoe of the pantograph type.

A still further object of my invention is to provide, in a collector shoe of the pantograph type, forremovably securing contact members of carbonaceous material and an associated guard member in operating relation.

l Another object cf my invention is to provide a'collector shoe comprising a body member on which a plurality of contact members of car bonaceous material are supported, which may beused interchangeably with collector shoes of l other forms on existing pantograph structures without altering the relation between the axis of support of the collector shoe and the contact surface thereof.`

I -Still another object of my invention is to provide a current collector shoe for use with structures of the pantograph type, which shall be of simple construction, inexpensive to manufacture and install, economical to maintain, and which have a 4relatively long life as compared to the 45 current collector shoes of the prior art.

Other objects will, in part, be obvious and will in part be explained hereinafter.

A preferred embodiment of my invention may comprise a plurality of contact members of carbonaceous material positioned in a channelshaped body member with suitable guard members for protecting the normally exposed edges of the contact members, and detachably secured therein by means of a centrally disposed wedge member.

; In order toi minimize corrosion of the body member through electrolytic action, the body member` is preferably provided with an insulating coating which isolates the contact members from the body member, and Aseparate conducting means are provided for the purpose of making electrical 5 connection with the Contact members independently of thev body member. With a view to reducing the number of renewal parts Which must bemaintained instock, the body member of the current collector shoe is so constructed that the 10 shoe may be used interchangeably with shoes of other forms on existing pantograph structures without changing or modifying the end horns of the structure. I

For a further understanding of the nature and 15 scope of my'invention, reference may be had to the following detailed description, ktaken in connection with the accompanying drawing, in which:

Figure 1v is a plan view of a current collector Q20 shoe embodyingthe principal features of my invention, complete with end horns;v

Fig. 2 is'a side viewof the current collector shoe of'Fig; 1;

Fig. 3 is an enlarged section View of the curx25 rent collector shoe o-f Fig. 1 along the line III-III;

Fig. 4 is -an enlarged plan view, in part, of the current collector shoe of Fig. 1;

Fig. 5 is an enlarged section View of the col- $3.0 lector shoe of Fig. 4, along the line V-'V; and

Fig. 6 is a section view of the current collector shoe of Fig. 4 along the line V'I-VI.-

Referring particularly to Figs. 1 and 2 of the drawing, the reference numeral I0 denotes a cur- 35 rent collector shoe of the pantograph type comprising, generally, a body member I2, a plurality of contact members I4, which are disposed to be positionedin the body member adjacent to'botn edges thereof, to provide a conductor engaging A0 contact surface, guard members I6 for protecting the 'normally exposed edges of the contact members I4, and a centrally disposed wedge member I8 for securing the contact members and guard members in operating relation with the 4 5 body member. Downwardly diverging end horns 20Vmay be secured to the ends yof the body member I2 for protecting the overhead line structure and providing for the positioning of the collector shoe on a pantograph structure (not shown). 50

By referring particularly to Fig. 3 ofthe drawing, it may be seen that the body member I2 comprises, preferably, an elongated channel section having upstanding sides 26 which are in- Wardly, inclined. Since the principal function 55 of the body member I2 of a current collector` shoe constructed according to my invention, is to support the contact members I4, it is desirable to utilize a construction affording the maxi- 5 mum strength with the minimum of weight. Ac-

cordingly, I prefer .to use an extruded channel section of a high strength aluminum alloy, the bottom of which is considerably thicker along the central portion than at the edges, and which may be provided with a longitudinal rib or bead 28 on the inner face of the sides 261 for purposes which will be hereinafter explained in detail. In` order to minimize corrosion of the body member I2, and protect it against electrolytic decomposition, I have found it desirable to at least cover the inside of the body member, and preferably the entire body member, with an insulating coating-- for example, an anodic oxide coating or a layer of a suitable insulating paint 29.

In order to make suitable electrical connection:

with the contact members I4 without conducting current through the body member I2, separate conductor members 30 may be provided comprising, for example, relatively thin copper strips or the like, disposed in the bottom of the body member I2 upon which the contact members I4 may be positioned. By extending the conductor members the length of the body member, separated therefrom by the insulating lm 29 and providing suitable connecting means, such as the connector 32, shown most clearly in Figs. 4, 5 and 6 at the ends thereof for making connection between the conductor members 30 and an external shunt member 34, suitable connection may be made with contact members I4 without requiring the body member I2 to carry any current, so that the body member will not be subject to decomposition through electrolytic reaction.

The contact members I4 comprise, preferably, molded carbon blocks which may be formed under pressure at a temperature which is suicient to evaporate the relatively low temperature hydrocarbons of the bond material used to bind the particles of carbon so as to obtain an integral mass of the necessary hardness to resist wear. It is, furthermore, desirable in many instances that the carbon blocks be impregnated with a lsuitable waterproofing compound so as to reduce the l porosity of the blocks and prevent deterioration through the entrance of water.

In order to eliminate grooving of the surface of the Contact members by an overhead trolley wire, I nd it desirable to make all joints between the contact members at an angle to the line of the trolley wire. Accordingly, the contact members I4 may be provided with substantially vertical divergent end faces so that when a plurality of the contact members are positioned in the body member I2 in end-to-end relation and in alternately reversed positions, the adjacent end surfaces of the contact members will be at an angle to the line of the trolley wire, as shown in Fig. 1.

An important feature of my invention is the manner in which the double row of contact members I4 are secured to the body member I2. With a View to simplifying the securing means as much as possible, provision is made for utilizing a single centrally disposed wedge member I8 for this purpose and providing the contact members I4 with sloping side faces disposed to be engaged by the wedge member I8 as best shown in Fig. 3. The wedge member I8 may be secured to the body member I2 by means of a plurality of bolts 4U.

In order to protect the leading and trailing edges of the contact members I4, the guard memf the body member when the bolts 4D are tightened to draw the wedge member I8 toward the body member. This not only secures the contact members I4 in the body member I2, but also urges 15 them downwardly against the conductor members 30 so as to ensure good electrical contact therewith, and outwardly against the guard members I6.

In order to eliminate any tendency for the body 20 member I2 to be deformed as the result of the force exerted along the center thereof by the bolts 4B, and thereby tilt the contact members I4, it is so formed, as shown in Fig. 3, that the bottom portion thereof is thicker at the center than at 25 the sides. The forming of the body member in this manner is easily made possible through the use of the extruded channel member,

In order to properly protect the contact members I4,it is desirable that the guard members I6 30 be composed of a, material which has not only sucient mechanical strength to provide the desired reinforcement for the edges of the contact members, but has also substantially similar wearing characteristics, so that it will not have a 35 tendency to groove or be cut by the overhead trolley wire, nor yet interfere with the current collecting function of the contact members. In this respect I have foundthat guard members comprising, preferably, a brous material im- 40` pregnated with a synthetic resin, such as, for example, fabric Micarta, give the most satisfactory results. They wear evenly and smoothly, reinforcing the edges of the contact members and preventing any tendency thereof to groove, yet 451 allow the contact members- I4 to be maintained in close engagement with the overhead conductor, so that the current collecting capacity of the collector shoe is not in any way reduced.

The end horns 26, which comprise downwardly 50 diverging guard members for protecting the supporting structure of the overhead conductor, may be secured to the body member I2 in any suitable manner, such as by means of bolts 45, which pass through depending side portions 46 of the end 55.

horns and the upstanding sides 26 of the body member, as shown in Figs. 4, 5 and 6. Associated openings in the body portion of the end horns 20 may be provided so as to define transverse ribs 49 and 50, having openings for receiving a sup- 60.

porting pin or axle 52, for securing the body member I2 of the collector shoe to the pantograph structure (not shown).

An important advantage of a collector shoe constructed in accordance with my invention over 65.

which brings the contact surface of the shoe 75' as close as possible to the axis of the supporting pins 52 in the horns 20, as is clearlyshown in Fig. 5 of the drawing. 'I'he result of this is to greatly reduce the frictional lmoment of force about the suppo-rting pins which prevents excessive wear at the edges of the contact members.

In order that a collector shoeconstructed in accordance with my invention may be used interchangeably with other forms of collector shoes on existing pantograph structures, an adapter 54 may be provided comprising a plate having rounded edge portions 56 and 51 for preventing cutting or marring of an overhead trolley wire, and notched end portions conforming closely with both'the end surfaces of the adjacent contact members I4 and the recessed portion 58 of the end horn 20,1; whichare disposed to receivethe ends of contact strips when used with a current collector shoe body member of another form. Suitable means, such as the screws 66, may be providedfor securing the adapter 54 tothe body member I2 of the collector shoe. By utilizing suitable spacer members 60 and 62 in connection with the screws 66, the screws 66 may be further utilized in providing for connection of the connector plate 32, the conductor members 3U, and the external connector member 32, so as to facilitate external connection to the contact members I4. Since the conductor members 30 are generally insulated from the body member I2 by the insulating film 29, it is not essential to `provide insulating means at the points where the screwsv 6B pass through the body member I2, since there will be no tendency for current to ilow through the body member at these points.

In view of the foregoing description, it is apparent that my invention provides a current collector shoe of the pantograph type which is of simpleand light weight construction and which .may be easily manufactured. Since the body member of the current collector shoe carries no current, it will not be subjected to electrolytic decomposition, and may be made from lightweight, high strength, aluminum alloys so that the collector shoe will have a minimum Weight and may be more readily made to follow irregularities in theV contour of the overhead conductor. The tendency of the collector shoe to spark may thus be reduced,` eliminating to a large extent an an- -noying source of radio interference.

By providing the carbon contact members with a guard memberof Micarta or the like, chipping and grooving of these contact members is reduced to a minimum, and the life thereof is greatly increased. The collector shoe may be readily used interchangeably with collector shoes of other types already in use on existing pantograph structures without requiring the use of other end horns, thus reducing the number of renewal parts which would otherwise have to be maintained at hand.

Since certain changes may be made in the above construction, and different embodiments of the invention may be made without departing from the spirit thereof, it is intended that all the ma*- ter contained in the above description or shown in the accompanying drawing shall be considered as illustrative and not in a limiting sense.

I claim as my invention:

l. A current collector of the pantograph type comprising, a body member, a removable contact member of carbonaceous material mounted thereon having an exposed Wear surface, and a non-metallic guard member secured to the body member to provide arenewable guard for reinforcing `an edge of the wear surface of the contact member.

2. A current collector shoe comprising, a me'- tallicbody member, a carbonaceous contact member supported by the body member to provide a wear surface for engaging a current carrying conductor, and a non-metallic guard member positioned adjacent the contact member tov provide a reinforcing edge for the-wear surface of the contact member. y

3. A current collector device comprising, a body member, a carbonaceous contact member supported by the body member and having a wear surface for engaging a current carrying conductor, a guard member of insulating material having wearing qualities similar to those of the contact member disposed'in engagement with the contact member for reinforcing an edge portion of the wear surface thereof, and means for securing the contact member in fixed relation with the body member.

4. A current collector for engaging an over-- head conductor comprising, a body member, a removable contact memberpositioned therein having an exposed wear surface, conductor means disposed in engagement with the contact member for providing an external connection to the contact member, a removable guard member of insulating material positioned along an edgev of the wear surface to provide a protective edge for reinforcing the contact member and insulating it from the body member, and wedge means for securing the contact member to the body member.

5. A current collector shoe for engaging an overhead conductor which comprises an elongated body member having upstanding sides, a plurality of similarly shaped contact members of carbonaceous material disposed in alignment on the body member with the` adjoining end faces thereof angularly disposed with respect to the longitudinal axis of the body member to provide anv elongated contact surface for engaging the conductor, guard members disposed between the contact members and the sides of the body member to provide a' reinforcing wear surface along an edge of the contact surface, and end means secured to the body member for supporting the collector shoe.

6. A collector shoe for a current collecting device comprising, a` body member, a plurality of contact members detachably, secured to the'body member to provide an elongated contact surface for engaging a conductor, means associated with the contact members for collecting current therefrom independently of the body member, insulating means removably secured to the body member for providing a reinforcing edge along an edge of the said contact surface for the contact members and insulating them from the contact members for providing a connection to the contact members independently of the body member, a guard member disposed to provide a reinforcing wear surface for the contact members, and a wedge member disposed to secure the contact members and the guard members in operating relation to the body member.

8. A collector shoe of the pantograph type comprising, -a channel-shaped body member, a plurality of contact members of carbonaceous material positioned in the body member, a conductor member disposed within the body member for eifecting connection to the contact members, a guard member disposed to provide a wear edge for the contact members, and means including a wedge member disposed to secure the contact members and the guard member in operating relation with the body member.

- 9. A current collector of the pantograph type comprising, a channel-shaped body member, a plurality of removable contact members of car-- bonaceous material positioned in the body member, a Micarta guard member disposed to provide a reinforcing wear edge for the contact members, and means cooperative with the contact members for securing the contact members and the guard member in fixed relation With the body member.

, 10. A current collector shoe comprising, an eX- truded channel-shaped body member, a plurality of contact members of carbonaceous material positioned in the body member having an exposed contact surface for engaging a conductor, conductor means disposed between the body member and the contact members to provide for external connection to the contact members, guard means disposed to provide a reinforcing edge for the contact surface of the contact members, and means for engaging the contact members to draw them into engagement with the conductor means and secure the guard means in fixed relation with the body member.

11. A collector shoe of the pantograph type comprising, a body member, a carbonaceous contact member supported by the body member having a wear surface for engaging a conductor, renewable guard means disposed between the contact member and the body member for reinforcing an edge of the wear surface of the contact member, means integral with the body member disposed in interlocking relation with the guard means, conductor means for engaging the contact member to provide electrical connection therewith, and means engaging the contact member to secure it in operating relation with the conductor means and the body member.

v 12. A collector shoe comprising, a channelshaped body member having upstanding sides, a

plurality of similarly shaped contact members of carbonaceous material positioned in overlap--4 ping relation between the sides of the body mem. ber to provide an elongated wear surface, removable guard members for protecting and reinforcing the edges of the Wear surface, end horns disposed to be secured to the body member,l means .engaging the contact members t secure the contact members and guard members in operating relation with the body member, and an adapter member disposed in overlapping relation witb. the end horns and the contact members to provide a substantially continuous wear surface.

13. A current collecting shoe comprising, a

channel-shaped body member having upstanding sides, a plurality of contact members of carbonaceous material supported in the body member to provide .a wear surface, a guard member 4of brous insulating material for protecting an edge of the wear surface of the contact members positioned between the contact members and the sides of the body member, a conductork member disposed within the body member to conduct current from the Contact members, insulating means positioned between the conductor member and the body member, means for securing the contact members and vguard member in operating relation with the body member and conductor member, and end means disposed to be secured to the body member for supporting the shoe about an axis adjacent to the surface of the contact members.

14. A collector shoe of the pantograph type comprising, an extruded channel member having upstanding lip portions with an integral projecting portion, a plurality of contaact members of carbonaceous material disposed in the channel member so as to provide an elongated contact surface for engaging a conductor, a guard member disposed to be secured in interlocking'relation with the integral projecting portions of the channel member to provide a reinforcing edge for the contact surface, a wedge member disposed to engage the contact members and secure the contact members and guard member to the channel member, end horns secured to the channel member for supporting the collector shoe, and adapter means comprising a plate member disposed in interlocking relation with the' contact members and the end horns to provide a smooth wear surface.

` i WILLIAM SCHAAKE. 

